Antietam battle so big, there are 2 re-enactments

The Civil War's Battle of Antietam was so big, they're re-enacting it twice.

Two private groups prepared large-scale recreations of the clash near Sharpsburg. The first was held last weekend near Boonsboro, Md. The second is this weekend near Sharpsburg, Md.

On Monday, the National Park Service will mark the 150th anniversary on the battlefield.

The first re-enactment aimed for realism. The rules governed everything from the type of shoes worn by soldiers to the number of cannons on the field.

This weekend's event is more of an extravaganza with 68 cannons and a hot-air balloon, even though there were no such aircraft at Antietam.

The battle on Sept. 17, 1862, was the bloodiest one-day clash of the war with 23,000 soldiers reported dead, wounded or missing.